AC
alternating current. 77, 215
AER
Annual Energy Review. 102, 103, 105-107, 109, 170
alpha decay
(a) happens when a nucleus emits an alpha particle, otherwise known as a *He nucleus. 243, 422, 435
alpha particle
(a) is a *He (helium) nucleus, ejected from a larger nucleus in an alpha decay It therefore consists of two protons and two neutrons. 243, 245, 422
Amp
(A) is short for Ampere. 77, 293, 422, 425
Ampere
(A, or Amp) is the SI unit of current, defined such that one Ampere is the same as one Coulomb per second (1 A 1C/s). 77, 422
a.m.u.
atomic mass unit. 241, 246-248, 253, 254, 265, 376, 422, 432, 433, 435
Annual Energy Review
is compiled by the U.S. EIA, capturing energy use and trends for all sources and sectors [^34]. 102, 170, 422
Astronomical Unit
(AU) is a unit of distance, equal to the average Earth-Sun distance of 149.6 million kilometers (1.496 x
asymmetric risk
describes a condition where given the choice to pursue action B for fear of some future condition instead of the normal action A, the downside of being correct about the threat and not taking action B is far more disastrous than being wrong about the threat and pursuing route B unnecessarily. 345, 351
atomic mass unit
(a.m.u.) is defined so that a single neutral carbon atom, consisting of 6 protons, 6 neutrons, and 6 electrons has exactly 12.00000 a.m.u. In other units, it is 931.4941 MeV or 1.66054 x
AU
Astronomical Unit. 56, 206, 420, 422
Avogadro’s number
is NA = 6.022 x 1023, pertaining to one mole of particles (e.g., atoms, molecules). 375, 376, 381, 433
band gap
is the energy difference between the conduction band and the valence band, determining how much energy is needed to promote an electron out of an atom and into conduction. 203, 204, 223
barrel
(bbl) is a unit of volume used primarily for petroleum. It is exactly 42 U.S. gallons, amounting to 159 L of volume. A commonly used measure of energy is barrels of oil equivalent (b.o.e.), amounting to 6.1 GJ of combustion energy. 112, 120, 126, 129-131, 135, 141, 211, 266
beta decay
(B) happens when a nucleus emits either an electron (ẞ ̄) or a positron (B). 243, 245, 265, 435, 438
Betz limit
is a theoretical maximum amount of kinetic power that can be removed from wind without slowing the wind too much. It computes to 19/27, or 59%, and is independent of technology [71, 72]. 188, 189, 195
Big Bang
is the name given to the start of the universe, about 13.8 billion years in the past. 9, 55, 239, 257, 392, 394, 396
biofuel
describes a liquid chemical fuel derived from biologically grown plants: algae, sugar, corn, rapeseed, etc. The two most common forms are ethanol and biodiesel. 165, 227, 230, 231, 428
biomass
is a generic term for biological matter, but in the energy context usually means firewood or dung that may be burned for thermal energy. 170, 227, 229-231
birth rate
quantifies the number of births per 1,000 people per year, typically. Numbers tend to be in the 5-30 range. 38, 426
blackbody
is a term describing the radiative qualities for thermal emission of light (infrared radiation for “normal” temperatures, becoming visible for very hot objects). A perfect blackbody is not reflective (i.e., “black” at the wavelengths of interest) and emits energy as a function of wavelength according to the Planck spectrum. 145, 199-201, 203, 223, 434, 438
boiling water reactor
is a type of nuclear fission reactor in which water surrounding the fuel rods acts both as a moderator and as the means of transporting heat away from the nuclear fuel. 255, 256
Boltzmann constant
is a fundamental constant of nature associated with thermodynamics. In SI units, it has a value of kB = 1.38 x
breeder reactor
is a nuclear fission reactor that transforms non-fissile nuclei into ones that are fissile by means of neutron capture and subsequent radioactive decay. 250, 262, 264, 296, 423
breeding
see breeder reactor. 259
British thermal unit
(Btu) is a unit of energy in the Imperial unit system, defined as the amount of energy required to heat one pound of water by 1°F. It is equivalent to 1,055 Joules. 75, 423, 427, 435, 437
Btu
is short for British thermal unit. 75, 97, 98, 335, 372, 423
Calorie
(Cal, or kcal) is a unit of energy, defined as the amount of energy required to heat one kilogram (1 kg, 1 L, 1,000 cm3) of water by 1°C. It is equivalent to 4,184 Joules, and is the exact same thing as a kilocalorie. Note the capital C differentiates it from the calorie, which is 1,000 times smaller, making this the dumbest unit convention around, and strongly favoring the use of the equivalent kcal instead. 73
calorie
(cal) is a unit of energy, defined as the amount of energy required to heat one gram (1 g, 1 mL, 1 cm3) of water by 1°C. It is equivalent to 4.184 Joules. 73, 85, 177, 194, 424, 431
capacity factor
is the fraction of energy delivered by an installation compared to what it would deliver if operating continuously at peak operating (“nameplate”) capacity. 176, 179, 180, 182, 183, 190, 191, 196, 212, 216, 217, 226, 256, 267, 279, 281, 282, 288
caprock
is a geological feature of impermeable rock that can trap oil, gas, or steam below it. 120, 278
carrying capacity
refers to the limiting population that can be supported long-term by the environment. No consensus exists for Earth’s carrying capacity for humans, though standards of living have a large influence. 34, 432
CFL
compact fluorescent light. 21
chain reaction
is a self-feeding process that keeps itself going. In the context of nuclear fission, neutrons released by the fission precipitate the next fission event, and so on. 251, 252, 255, 262, 425, 432
charge
is a measure of the degree to which a particle or object is influenced by electromotive forces. Electric charge can be positive or negative, so that like charges repel and opposites attract. The unit for electric charge is the Coulomb. 77, 240, 241, 246, 395, 425, 427, 429, 433
Chart of the Nuclides
is a Periodic Table on steroids, listing the properties of every known nuclide including mass or energy, abundance (if stable), half life (if unstable), decay mode, neutron cross section, nuclear spin, and other salient properties; see https://people.physics.anu.edu.au/-ecs103/chart/. 240-242, 244, 245, 248, 251, 253, 259, 266, 270
chemical energy
is energy stored in chemical bonds, like gasoline or wood that might be burned, or in the food we eat. 70, 117, 121, 182, 227, 228, 234, 379, 395, 396
climate sensitivity parameter
relates a change in radiative forcing to the net temperature change once all the feedback mechanisms have acted. The units are °C per
coefficient of performance
(COP) refers to the energy gain by a heat pump, usually in the context of heating rather than cooling. It is identical to Ɛheat, as defined in Eq. 6.11 (p. 95). 97, 425
compound
describes a particular combination of elements that construct a particular molecule. For instance, H2O is the compound we know as water. 376, 379, 432
concentrated solar power
(CSP) refers to a form of solar thermal (ST) energy, employing troughs or “power towers” or any technique that focuses solar power to create high temperatures, often then used to generate electricity. 220, 425, 436
conduction band
is the energy level a step up from that of electrons in the valence band. Electrons in the conduction band are very loosely bound and freely wander about the crystal, hopping from one atom to the next, and therefore able to contribute to a current. 202, 203, 422, 435, 438
confinement
in the context of fusion refers to the trapping and holding of a high-temperature plasma, usually by magnetic means. 265
conservation of energy
says that energy is never created or destroyed, only shifting from one form to another. 70, 91-93, 95, 246, 393, 394, 425
conservation of mass-energy
extends conservation of energy to include mass, so that the combined mass-plus-energy of a closed system is never created or destroyed, only shifting from one form to another (mass-energy exchange via E = mc2). 246
control rod
is used in a nuclear fission reactor to absorb neutrons so that the chain reaction does not get out of control and cause a meltdown. 251, 255, 256, 432
COP
coefficient of performance. 97, 99, 335, 424
Coulomb
(C) is the SI unit of electric charge. An electron has a charge of -1.6 x
coupled
refers to the tight connection often seen between energy/resource use and economic scale (as measured, for instance, by GDP). 18, 425
critical mass
is the mass of fissile material (assumed to be in spherical form) above which a self-sustained chain reaction will occur. Below this, the material poses no danger. Right at critical mass, the material will limp along in a slow chain reaction. Above this threshold-super-critical-an exponential runaway detonation will occur, and is the basis of nuclear weapons. For 235U, critical mass is 52 kg (a bit smaller than a volleyball), and for 239Pu, it is 10 kg, and about the size of an American softball. 262
CSP
concentrated solar power. 220, 424, 436
current
is a measure of charge flow, expressed in the SI unit of Amps. 77, 85, 202, 203, 205, 422, 425, 436
D-D fusion
uses deuterons (2H nuclei) as the fuel for fusion, achieving an energy density of 137 million kcal/g. 265
death rate
quantifies the number of deaths per 1,000 people per year, typically. Numbers tend to be in the 5-30 range. 38, 426
decay chain
refers to a consecutive series of radioactive decays. 244, 245
decoupling
is the notion that economic activities need not incur a large energy or resource cost, breaking the tendency for economic scale to be tightly coupled to physical goods. 20
demographic transition
refers to the process in which an undeveloped country initially having high birth rate and high death rate transitions to low death rates followed by low birth rates as medical and resource conditions improve. 39, 44
deuterium
is an isotope of hydrogen, in which the nucleus (called a deuteron) contains one proton and one neutron. 248, 265, 266, 272, 274, 299, 426
deuteron
is the nucleus of deuterium, consisting of one proton and one neutron. 265, 425, 426
dietary energy factor
is the quantitative energy impact of a set of dietary choices compared to a vegetarian diet. A typical American diet has a dietary energy factor around 2, meaning it takes twice as much energy as would a vegetarian diet. This term is not in universal use. 339-341, 349, 428
differential equation
is an equation that relates functions and their derivatives. The subject is often sequenced after calculus within a curriculum. 33, 34
doping
is a process by which deliberate impurities are introduced into a semiconductor in order to change its properties with respect to transport of electrons or holes. 202, 431
doubling time
is how long it takes a system or collection to double its amount under conditions of growth, such as in exponential growth. See also the rule of 70. 2, 6, 23, 31, 32, 405
D-T fusion
combines a deuteron (2H nucleus) and a triton (3H) as the fuel for fusion, achieving an energy density of 81 million kcal/g. 265, 267
duty cycle
refers to the percentage of time something is “active.” For example, a refrigerator may be on 40% of the time to maintain internal temperature, in which case its duty cycle is 40%. 88, 334
Ecological Economics
is a field that builds economic theory on top of the notion that the planet offers finite resources and flows. A principle aim is that of a steady-state economy capable of indefinite planetary compatibility. 323, 324
EER
energy efficiency ratio. 97-99, 427, 430
EIA
Energy Information Administration. 7, 75, 102, 103, 106, 107, 131, 170, 215, 422, 426
Electric Power Monthly
(EPM) is compiled by the U.S. EIA, capturing electricity production and usage at the state level from all energy sources [^85]. 215, 427
electromagnetic radiation
refers to any transport of energy by electromagnetic waves, which include light, ultraviolet, infrared, X-rays, microwaves, gamma rays, and radio waves. 10, 198, 397, 426, 431, 435
electromagnetic spectrum
refers to the sweep of wavelengths or frequencies of electromagnetic radiation, including light, ultraviolet, infrared, X-rays, microwaves, gamma rays, and radio waves. 79, 392
electron
is a fundamental particle typically found in the outer parts of atoms, surrounding the nucleus. Electrons have negative charge equal and opposite to that of protons, but are 1,836 times lighter than the proton, at 0.511 MeV. 77, 78, 198, 202, 239, 244, 245, 255, 395, 422, 423, 425, 426, 429, 430, 433-435, 438
electron-volt
(eV) is a unit of energy, defined as the energy (work) it takes to push a charge of one fundamental charge unit (see entry for Coulomb) through an electric potential of one Volt. 1 eV is equivalent to 1.6 x
element
pertains to a single atom on the Periodic Table. For instance, hydrogen, helium, and carbon are all elements. 376, 379, 424, 432
energy
is defined as the capacity to do work. The SI unit is the Joule. 68, 73, 77, 174, 334, 379, 423-425, 427, 431, 434, 437, 438
energy density
describes how concentrated energy is in a substance, quantified as energy per unit mass. In chemical contexts, anything around 10 kcal/g or higher is considered energy-dense, while substances at about 1 kcal/g or lower are poor. Carbohydrates and proteins are middling, around 4 kcal/g, while fat is 9 kcal/g, and therefore among the more energy-dense substances. 121, 122, 175, 228, 230, 231, 236, 237, 254, 256, 264, 277, 290, 380, 398, 425, 426, 428
energy efficiency ratio (EER)
refers to the energy gain by a heat pump, usually in the context of cooling rather than heating. Its units are odd, defining how many British thermal units (thermal energy) may be moved per Watt-hour of input energy, but relating to Ecool (defined in Eq. 6.10 (p. 95)) by a simple numerical factor: EER = 3.41&cool. Sometimes seen as SEER to represent a seasonal average EER value. 97, 98, 426
energy intensity
measures the energy use of a society relative to its economic scale. A typical value may be about 5 MJ/$. 19, 336
energy trap
refers to a phenomenon in which energy shortage motivates aggressive pursuit of alternative energy schemes, but that pursuit requires substantial energy investment-forcing an even more acute but voluntary energy shortage, which is politically difficult. 132, 301, 310, 311
enriched
see enrichment. 258, 262
enrichment
refers to the process of increasing the concentration of a particular isotope within a sample of an element. Usually, this term is applied to the concentration of 235U from its natural 0.72% to 3-5% for power plants or >20% (typically ~85%) for weapons. 258, 427
entropy
is a measure of how many ways a system can be configured for some fixed energy level. The entropy of a closed system cannot decrease. 90, 396, 420
Environmental Economics
is an offshoot of neo-classical economics that adds a layer of pricing to capture “externalities,” or environmental costs not normally included in market price. 323
EPM
Electric Power Monthly. 215, 426
Energy Returned on Energy Invested
a measure of how profitable an energy source is in terms of energy, expressed as a ratio. For instance, a 9:1 EROEI means 9 units were extracted or produced for an investment of 1 unit, leaving a net gain of 8 units of energy. 1:1 is break-even, deriving no net energy benefit. 231, 235, 236, 278, 295, 297, 301, 302, 310, 311, 315, 339
estimated total resource
is an educated extrapolation of proven reserves trying to characterize the amount of resource that may be ultimately found and extracted. 127, 131, 258
ethanol
(C2H5OH) is a liquid alcohol frequently produced as a biofuel having an energy density of ~7 kcal/g. 108, 230, 297, 377, 423
eV
electron-volt. 198, 203, 248, 427, 432
exponential growth
happens when the rate of growth-as a percentage or fraction-is constant. 2, 4, 31, 33, 61, 319, 426, 434
feedback
is the response of a system when a change is made that itself influences the change: either counteracting it as in negative feedback or amplifying it as in positive feedback. 145, 147, 424
fill factor
is a generic term describing the fraction of total area occupied. For instance a polka-dot pattern of circles on a piece of fabric might have a fill factor of 15%. 189
fissile
describes a nucleus that is prodded into fission by a (slow) thermal neutron. The three fissile nuclides of interest are 233U, 235U, and 239Pu. 255, 259, 262, 423, 425, 428
fission
is a nuclear process in which a heavy nucleus splits into two lighter nuclei. Only 233U, 235U, and 239Pu are usually considered as accessible nuclides that are fissile in the presence of slow (thermal) neutrons. 85, 239, 249, 264, 289, 296, 423-425, 428, 432
flexitarianism
is the practice of pursuing dietary choices based on quantitative assessment of energy costs in an effort to keep the dietary energy factor low, without enforcing complete strictness, enjoying the occasional deviation on special occasions or just to avoid being a pain to others. 342
fossil fuel
refers to an energy source buried in the ground, in the form of coal (solid), petroleum (liquid), or natural gas (gaseous). Fossil fuels represent ancient solar energy captured in living matter, processed and stored underground over millions of years. 7, 22, 27, 31, 61, 103, 104
fracking
is slang for hydraulic fracturing, a technique used to extract “tight” oil and gas resources locked up in less permeable rock formations. High-pressure fluids are used to create cracks in the rock that the allow oil and/or gas to flow. 120, 124, 128, 130, 232
frequency
characterizes the number of cycles per second in a periodic phenomenon (often in wave phenomena). The units are Hertz, or 1/s. 79, 198, 426, 430, 434, 436
fuel rod
is a long cylinder having a high-enough concentration of fissile material to be used in a nuclear fission reactor. 255, 256, 260, 263, 272, 423
fusion
is a nuclear process in which two light nuclei merge to form a larger nucleus. Repulsion of the charges in the nuclei make it exceedingly hard to achieve, requiring temperatures of many millions of degrees. 85, 239, 249, 265, 289, 299, 395, 425, 426, 437
galaxy
is a collection of stars held together by mutual gravitational attraction, generally numbering in the billions of stars. 9, 54, 55, 312, 394, 438
gamma decay
(y) is when a nucleus in an energetically excited state emits a high-energy photon. 244, 429, 435
gamma ray
(y) is a high-energy photon, as may be generated by a gamma decay or by annihilation of an electron and positron. 244, 251, 255, 434, 435
GDP
Gross Domestic Product, effectively representing the total monetary flow of goods and services within a society, typically over a one year period. 18, 24, 39, 425
generator
converts mechanical motion (rotation, typically) into electrical current, generally by the relative motion of wire loops and a strong magnetic field. 89, 99, 164, 165, 175, 184, 185, 190, 250, 279, 280, 282, 285, 430, 436
geothermal
refers to thermal energy within the earth, both from the original heat of formation and from radioactive decay. 85, 99, 108, 166, 275
GHG
greenhouse gas. 146, 151, 152, 155, 160, 161, 429
Gppl
is a short-hand unit for giga-people, or billion people. 32, 37
gravitational potential energy
is the energy stored in a mass, m, lifted a height, h, above some reference in the presence of gravity, g≈ 10 m/s2. The energy amounts to mgh, and will be in Joules if the inputs are in kg, m, and s. 66, 69, 70, 77, 89, 167, 173, 174, 177, 184, 275, 280, 283, 395, 396, 438
Green Revolution
refers to the modernization of agricultural practices worldwide beginning around 1950, when fossil fuels transformed both fertilization and mechanization. 31, 37, 123, 124, 234
greenhouse gas
(GHG) absorbs infrared radiation and acts as a thermal blanket in a planetary atmosphere. H2O, CO2, 03, and CH4 are powerful greenhouse gases. 11, 12, 144-146, 151, 429
grid tied
refers to a photovoltaic system connected to the local electrical utility grid, enabling export of solar production by day and use of utility electricity by night. 213, 222
half life
is the time after which half a sample of radioactive nuclei will have undergone radioactive decay. After N half-life periods, the remaining fraction will be 1/2N. 242, 243, 257, 259, 261, 262, 270, 276, 424, 435
heat capacity
is the amount of energy it takes to raise an object’s temperature by 1°C. The specific heat capacity is the heat capacity divided by mass, becoming an intrinsic property of the material. Water’s
specific heat capacity
is 4,184 J/kg/°C, intimately tied to the definition of the kilocalorie. 74, 85, 99, 147, 153, 168, 194, 271, 277, 372, 401
heat engine
is a device that converts thermal energy into another form, usually mechanical motion. Automobile engines are a common example, as are power plants that create steam from a thermal source that itself drives a turbine and generator. 89, 92, 165, 239, 267, 276, 277, 286, 294, 298, 348, 396, 433, 436.
heat loss rate
as used in this book is the power per AT (in °C) required to maintain a temperature differential. Units are W/°C, and typical houses might be a few hundred W/°C. 87, 99, 100, 334
heat of fusion
is the energy barrier associated with either forming (fusing) or melting a solid from a liquid. In the case of water (ice), the heat of fusion is 334 J per gram. 152, 153
heat of vaporization
is the energy barrier associated with turning a liquid into gas. In the case of water going to water vapor, the heat of vaporization is about 2,250 J per gram. 177
heat pump
is a device that moves thermal energy from a cold environment to a hotter one, against normal flow. Some energy input is required to drive this reverse flow, but thermodynamic principles permit a small amount of input energy to drive a larger amount of thermal energy transfer. 85, 95, 297, 335, 427, 430
heating seasonal performance factor
(HSPF) refers to the energy gain by a heat pump in the context of heating, but in the same units as the EER so that HSPF is COP times 3.41, numerically. 97, 98, 430
heavy oil
refers to oil that is very viscous-closer to tar than to gasoline. Heavy oil is more difficult to extract, process, and obtain gasoline via refinement. 131
Hertz
(Hz) is the SI unit for frequency, and is equivalent to cycles per second, or 1/s. 198, 428
hockey stick
is a term used to describe plots that suddenly shoot up after a very long time of relative inaction. Plots of human population, atmospheric CO2, energy use, all tend to show this characteristic which resembles an exponential curve. 31, 115
hole
in the context of semiconductors is the absence of an electron-or an electron vacancy. When another electron fills the hole, it leaves behind another hole, and it is as if the hole movedeffectively like a positive charge able to roam through the crystal. 202, 204, 426, 435
HSPF
heating seasonal performance factor. 97-99, 430
HST
Hubble Space Telescope. 59
hydrocarbon
is a chain of carbon and hydrogen atoms such as the alkanes (methane, ethane, propane, butane, octane, etc.) having chemical formula CnH2n+2, where n = 1 for methane, 2 for ethane, 8 for octane, etc. 119, 121, 131, 229, 436
hydrological cycle
is the solar-driven process by which evaporation of water from the surface (bodies of water or moist land) forms clouds, and the clouds deliver rain back to the surface. 166, 168, 177
infrared radiation
is the property that all objects glow in light, or electromagnetic radiation. For objects that are not “red hot,” the emission is invisible to the human eye, at longer wavelengths than the visible spectrum. The power radiated obeys the Stefan-Boltzmann law. 10, 84, 143, 147, 151, 161, 169, 396, 397, 423, 429, 435, 437
insolation
is the annual average solar flux reaching flat, level ground for a particular location. A typical number is 200
inverse function
is a mathematical operation that “undoes” its counterpart, like the square root undoes the square, or the natural logarithm undoes the exponential. 5, 32, 367, 370
isotope
is what we call atoms that have various nuclear configurations for the same element. That is, variants of a nucleus having the same number of protons but differing numbers of neutrons, and therefore differing mass number. See also nuclide. 240, 242, 252, 261, 266, 296, 375, 376, 426, 433, 437
ISS
International Space Station. 58-60
Jevons paradox
is named after early economist William Stanley Jevons, and describes the backfire of efficiency improvements leading to increased usage of the associated resource due to greater demand for the more attractive, efficient technology. Also called the rebound effect. 23, 435
Joule
(J) is the SI unit of work or energy, and is equivalent to Newtons times meters (Nm), or kg m2/s2. 19, 69, 159, 309, 371, 420, 423, 424, 427, 429, 431, 432, 434, 435, 437, 438
junction
describes an interface between two semiconductors that have different doping. Junctions are the basis of photovoltaic, diodes, light emitting diodes (LEDs), transistors, and many light detectors. 202, 204
kcal
kilocalorie. 74, 85, 99, 118, 121, 122, 136, 140, 228-230, 233, 236, 237, 246, 253, 254, 258, 265, 277, 290, 334, 335, 339, 340, 380, 398, 423-428, 431
Kill-A-Watt
is the name of a relatively inexpensive device that can measure instantaneous power in Watts and accumulated energy in kWh of electrical appliances. The name is a pun on units. 334
kilocalorie
(kcal) is a unit of energy, equivalent to 1,000 calories, defined as the amount of energy required to heat one kilogram (1 kg, 1 L, 1,000 cm3) of water by 1°C. It is equivalent to 4,184 Joules. 73, 84, 254, 334, 339, 424, 430, 431
kilowatt-hour
(kWh) is a unit of energy, constructed as a power (kilowatts) times time (hours). It is equivalent to 3,600,000 Joules, or 3.6 MJ. 72, 159, 172, 209, 214, 226, 343, 401, 402, 432
kinetic energy
is the energy of motion, given by mo2 for a mass, m, at velocity, v. If input units are kg and m/s, the resulting unit will be Joules. 69-71, 89, 174, 184, 185, 223, 275, 282, 284, 395, 396, 437
kWh
kilowatt-hour. 76, 159, 214, 272, 334, 335, 337, 338, 342, 348, 398, 431, 438
LED
light emitting diode. 21, 29, 78, 83, 431
life-cycle CO2 emission
is an assessment of how much CO2 is released from an energy source when considering the entire enterprise—including manufacture/construction, operation, etc. See the Wikipedia page on List of life-cycle greenhouse gas emissions. 181, 194, 218, 221, 264
liquefied natural gas
(LNG) is cryogenically-cooled natural gas (methane) at -160°C that can be stored much more compactly than the gaseous form, making it suitable to transport. 432
LNG
liquefied natural gas. 121, 432
logistic
describes a mathematical model in which rate of growth depends on how close the population is to the carrying capacity. The resulting population curve over time is called the logistic function, or more informally, an S-curve. 34
macro-economics
concerns itself with the allocation of goods and services across the marketplace, optimizing supply and demand, aiming to minimize surplus or deficits. 323, 324, 433
mass number
(A) is simply the total number count of protons and neutrons (nucleons) in a nucleus. For example, a carbon atom having 6 protons and 6 neutrons has A = 12. 240, 431
meltdown
refers to a failure mode of nuclear fission reactors, in which the chain reaction becomes uncontrolled due to too many neutrons triggering new fission events (as may happen if control rods are absent or insufficiently deployed). 262, 263, 425
MeV
is a mega-electron-volt, or
micro-economics
concerns itself with the production of goods, including raw resources, marketing, and distribution. 323, 324, 433
micron
(um) is
moderator
in the context of nuclear fission is a material used to slow down neutrons speeding out from the break-up so that they can become thermal neutrons and stimulate subsequent fission events in a chain reaction. Light atoms like water are a good choice for absorbing the neutron impacts. 251, 255, 256, 423
molar mass
is the mass of one mole of an element or compound. The molar mass for carbon, for instance, is 12 grams. The number is often found on a Periodic Table, in addition to the proton number for the element. 121, 138, 241, 379, 380
mole
is a number of atoms or molecules, tuned so that one mole of the carbon-12 isotope is exactly 12.000 grams. It takes 6.022 ×
negative feedback
involves a reaction to some stimulus in the direction opposite the stimulus, performing a corrective action and leading to stability. Systems in equilibrium must have negative feedback keeping them there. 33, 123, 147, 428, 433
neo-classical economics
is the prevailing economic regime practiced today, driven by supply and demand, fueled by growth, market investment, and focus on micro-economics and macro-economics. 323, 427
neutrino
is a fundamental particle associated with the weak nuclear force that has almost no mass, travels near the speed of light, and interacts so weakly with matter that it could pass through light-years of rock before being likely to hit anything. Neutrinos from the sun stream through our bodies constantly, day and night, since Earth is transparent to them. 243, 244, 438 neutron is one of two basic building blocks of atomic nuclei, the other being the proton. Neutrons have no electric charge, and a mass of 939.565 MeV, or 1.008665 atomic mass unit (a.m.u.). Neutrons are made up of three quarks: 1 up and 2 down. 240, 243, 244, 255, 299, 375, 376, 395, 422-426, 428, 431-433, 435, 437, 438
Newton
(N) is the SI unit of force, and is equivalent to kg m/s2. 68, 371, 431, 438
nuclear binding energy
is the energy associated with the strong nuclear force that holds a nucleus together against charge repulsion. Typical levels are 8 MeV per nucleon. 247, 248
nuclear energy
derives from reconfiguring the nuclei of atoms, releasing tremendous thermal energy that can be harnessed in a heat engine. 103, 104, 239
nucleon
is either of the two building blocks of a nucleus, meaning that it is either a proton or a neutron. 240, 247, 248, 251, 376, 432, 433, 437
nucleus
is at the center of an atom, composed of protons and neutrons and spanning~
nuclide
is any bound arrangement of protons and neutrons. Every nucleus of every isotope is one of the possible nuclides, designated, for instance as C12, C-12, or 12C. 240, 242, 243, 424, 428, 431, 435
overshoot
occurs when the negative feedback in a system is delayed. After surpassing the equilibrium, oscillation may ensue. 36
parts per million
(ppm) is a unit used to measure small contributions. One ppm is 0.0001%. 61, 139, 141, 434
parts per million by mass
(ppmm) is a parts per million measure in terms of fractional mass. For instance, a gram is is 1 ppmm of a metric ton (1,000 kg). 141, 258
parts per million by volume
(ppm) is a parts per million measure in terms of fractional volume occupied. For instance, a cubic millimeter (1 μm, or micro-liter) is 1 ppm, of a liter. 140-142
payback time
is how long it takes to recuperate an investment by removing a chronic cost. For example, spending $1,000 to no longer pay an annual $100 charge has a payback time of 10 years. 215, 226
photon
is the smallest indivisible particle of light: a minimum quantum packet of energy. Each photon has a well defined energy, which can also be expressed as a wavelength or frequency. 21, 70, 78, 79, 198, 199, 202, 227, 243, 244, 251, 394-396, 429
photosynthesis
is the process by which living matter captures sunlight and stores some of it as chemical energy. Effectively, it takes CO2 out of the atmosphere, combines the carbon with water to make sugars, releasing oxygen back into the air. 227, 395
photovoltaic
(PV) is a semiconductor technology by which light directly drives an electrical current by interacting with electrons in the material. 165, 197, 201, 217, 218, 239, 267, 289, 292, 315, 350, 429, 431, 435
Planck spectrum
describes a mathematically precise spectrum of light emission from a blackbody, fully defined by the temperature of the blackbody. 145, 199-201, 423, 436, 438
Planck’s constant
is a fundamental constant of nature associated with quantum mechanics and the world of the very small. In SI units, its value is h = 6.626 x
plasma
is a gas hot enough to strip electrons from atoms to create a highly-ionized medium, such as the gas comprising the sun. 265, 267, 268, 392, 393, 395, 425, 437
positive feedback
involves a reaction to some stimulus in the same direction as the stimulus, thus amplifying the effect. Positive feedback leads to an unstable, runaway process-like exponential growth. 33, 123, 147, 428
positron
is an elementary particle of anti-matter, and specifically an anti-electron, having the same mass and opposite charge as the electron and will annihilate with an electron into gamma rays. 243-245, 255, 423, 429
power
is the rate of energy, or change in energy per change in time. The units are Joules per second (J/s), or Watts (W). 7, 10, 11, 30, 43, 71, 73, 77, 86, 110, 118, 146, 151, 171, 176, 187, 205, 280, 334, 335, 368, 373, 431, 435-438
ppm
parts per million. 61, 139, 141, 433, 437
predicament
describes a seemingly intractable situation: more than a problem, but possibly a tangled set of interconnected problems. Predicaments require responses rather than tidy solutions. 332, 436
proliferation
is used to describe widespread distribution of dangerous nuclear materials, which becomes difficult to control if they exist in abundance due to increased reliance on nuclear energy. 239, 260, 262, 264, 269, 296, 297
proton
is one of two basic building blocks of atomic nuclei, the other being the neutron. Protons have positive charge, equal and opposite to that of the electron. Protons have a mass of 938.272 MeV, or 1.0072765 a.m.u.. Protons are made up of three quarks: 2 up and 1 down. 77, 240, 243, 244, 375, 376, 395, 422, 425-427, 431-433, 437, 438
proven reserve
pertains to the amount of resource known to exist, having been discovered and surveyed to estimate the economically recoverable amount. 126, 127, 131, 257, 258, 267, 269, 428
PV
photovoltaic. 165, 197, 201, 205, 217, 220, 221, 267, 269, 281, 292, 293, 434
qBtu
is short for a quadrillion (1015) British thermal units, and is equivalent to 1.055 x
R/P ratio
or reserves-to-production ratio is a means to assess time remaining for a resource of quantity R units, being used (produced) at a rate of P units per year. The result is years available at the present rate, absent discovery of additional resources or change in rate of use. 126, 129, 131, 133, 136, 267
radiation
is a broad term that can can describe light (e.g., electromagnetic radiation, infrared radiation, gamma rays) or particles from radioactive decay or cosmic origin. High-energy radiation of any form can cause damage to materials and biological tissues (DNA being perhaps most critical). 263
radiative forcing
is used to describe the areal power (in
radioactive
describes a nucleus, or nuclide that is unstable and will undergo radioactive decay with some half life. 241, 257, 260, 261, 263, 268, 276, 296, 297, 299, 429
radioactive decay
involves a change in the nucleus of an atom, most commonly in the form of alpha decay, beta decay, or gamma decay. 239, 242-244, 262, 275, 297, 423, 425, 429, 435, 437
rebound effect
describes the counterintuitive process by which efficiency improvements lead to greater use of the resource as the enhanced appeal and lower cost results in more widespread adoption and use. Also called the Jevons paradox. 23, 431
recombination
is when an electron in the conduction band of a semiconductor finds a vacancy (hole) for it to settle into. By disappearing from the conduction band, it is no longer available to contribute to current, and the energy it had becomes unrecoverable. 202, 204
refinement
is the process by which crude oil—as it comes out of the ground-is separated by approximate hydrocarbon chain length. In order of lighter/shorter to heavier/longer chains, crude oil yields propane and butane, gasoline (around octane), kerosene, diesel, heating oil, lubricating oil, and tar. 119, 430
renewable
forms of energy are not necessarily depleted by their use. In other words, the resource is replenished naturally at some rate. The sun will still shine and wind will still blow even if we harness some of the energy. Firewood will grow back, but at a limited rate. 103, 104, 106
response
is an appropriate reaction to a predicament, which may fall well short of a solution, but still represents a reasonable compromise approach. 332, 434
rule of 70
tells us that the time it will take a system or collection to double in size is 70 divided by the percentage growth rate. The time units depend on how the time over which percentage growth is expressed-like 2% per day or 2% per year, for instance. The rule works most accurately for smaller growth rates, under 10%. 2, 5, 6, 28, 31, 405, 426
R-value
describes the thermal resistance, or insulating quality of a wall or similar barrier. It is an inverse to the U-value, numerically 5.7/U. Units are °F -ft2 hr/Btu, and larger numbers translate to better insulation. 87, 438
sea level rise
is one of the inevitable consequences of climate change, as land-bound ice melts and ocean water thermally expands. 151, 155
sector
refers to a domain of activity, typically dividing into residential, commercial, industrial, and transportation. 104, 165, 193, 337
semiconductor
is a material poised between being a good conductor of electrical current and an insulator (not passing current). Silicon is the most commonly used semiconductor. 201, 202, 426, 430, 431, 435
SI
Système International. 68, 71, 85, 88, 422, 423, 425, 427, 430, 431, 433, 434
solar constant
measures 1,360 $W/m^2$, and is the power flux of the sun at the top of Earth’s atmosphere. It is not technically a constant, but is very stable. 11, 144, 167, 203, 206, 211
solar system
refers to our own star, the sun, and the planets that surround it, including Earth. 54
solar thermal
(ST), also called concentrated solar power (CSP), typically refers to troughs or “power towers” or any technique that focuses solar power to create high temperatures, often then used to generate electricity via a heat engine and generator. 165, 197, 219, 221, 424, 436
spectrum
describes a distribution, often associated with light. In this context, a light spectrum specifies how much light is present as a function of wavelength or frequency. The Planck spectrum is a good example. 145, 200, 434
ST
solar thermal. 219-221, 269, 424, 436
Stefan-Boltzmann constant
(a) has a value of 5.67 x $10^{-8}$ $W/m^2$/K4 and is used in the Stefan-Boltzmann law relating to infrared radiation. 10, 144, 199, 437
Stefan-Boltzmann law
says that the power emitted from a surface of area, A, and temperature, T will be P = AσT4, where σ is the Stefan-Boltzmann constant. 10, 144, 199, 431, 437
stoichiometry
amounts to the counting of atoms and balancing formulas in chemical reactions to reflect the survival of every atom in a reaction: none created or destroyed. 377, 378
strong nuclear force
is the force that binds nucleons together in a nucleus, overcoming the electrical repulsion of protons. 240, 245, 247, 395, 433, 438
substitution
refers to interchangeability between goods and services, so that an unavailable or inferior resource can be replaced by an alternative, possibly superior one. 21
terraforming
is the speculative idea of transforming the atmosphere and environment of a planet hostile to human life into one that is suited to human needs. 60, 61
Therm
is a unit of energy defined as 100,000 British thermal units, and is equivalent to 1.055 × $10^{8}$ Joules. 76, 335, 337, 348
thermal energy
is the energy of heat, and is really just randomized kinetic energy (motion) of atoms and molecules vibrating and zipping around. 70, 71, 84, 86, 89, 99, 165, 194, 203, 227, 246, 275, 277, 294, 334, 335, 373, 395, 396, 401, 420, 423, 427, 429, 430, 433
thermal equivalent
is a construct used to compare thermal energy sources like coal, oil, and natural gas to sources like solar, wind, and hydroelectricity, which do not derive from thermal sources. Usually in the context of electricity production, multiplying by about 2.7 puts non-thermal sources into thermal-equivalent terms. 106-108, 170, 256, 279
thermal expansion
describes how materials expand, or swell, as temperature increases. Typical rates of expansion are in the range of 5-100 ppm per °C. 155
thermal neutron
is a neutron whose kinetic energy (speed) is no greater than it would naturally possess based on the temperature of its surroundings. Sometimes it is called a “slow” neutron because it is not traveling faster than thermal jostling would establish. 250, 428, 432
tokamak
is the name of a donut-shaped chamber in which high-temperature plasma can be confined, and potentially used to generate fusion. 267
transmutation
describes the transformation of a nucleus into a different one, usually via neutron absorptionpossibly followed by radioactive decay. 259, 268
tritium
is an isotope of hydrogen, in which the nucleus (called a triton) contains one proton and two neutrons. 265-268, 299, 438
triton
is the nucleus of tritium, consisting of one proton and two neutrons. 265, 426, 437
turbine
is essentially fan blades on a rotating shaft, which can be compelled to move by a flow of air, water, or steam through the blades. 89, 99, 164, 175, 185, 190, 250, 279, 280, 282, 295, 430
universe
refers to the entirety of our physical realm, including all galaxies. 9, 54, 55, 257, 312, 392, 423
U-value
describes the insulating quality of a wall or similar barrier, in terms of how many Watts move through each square meter of surface area for each 1°C difference in temperature across the barrier. Units are $W/m^2$/°C, and smaller numbers mean better insulation. The U-value is an inverse measure to the R-value, numerically 5.7/R. 87, 436
valence band
is the energy level of outer electrons bound to an atom. Valance electrons stay home, as opposed to electrons in the conduction band. 203, 422, 425
Volt
(V) is a unit of voltage, or electric potential, and can be thought of as the electrical analog to gravitational potential energy, and is also somewhat like pressure in a fluid system. 77, 198, 427, 438
voltage
is a measure of electric potential energy, expressed in units of Volts. 77, 438
Watt
(W) is a unit of power, defined so that 1 W is 1J/s (one Joule per second). 7, 18, 21, 43, 71, 77, 118, 169, 196, 267, 309, 371, 431, 434, 438
watt-hour
(Wh) is a unit of energy, constructed as a power (watts) times time (hours). It is equivalent to 3,600 Joules, or 0.001 kWh. 73, 77, 97, 110, 176, 427, 438
wavelength
measures the length of a wave from crest to crest or trough to trough, and can apply to waves in water, air (sound), or electromagnetic waves (light). The symbol A (lambda) is often used to denote wavelength. The units are length (m), often expressed in microns (um). 79, 144, 198, 283, 394, 426, 431, 434, 436
weak nuclear force
joins gravity, electromagnetism, and the strong nuclear force as one of nature’s four fundamental forces, responsible for beta decays and neutrino interactions. 244, 245, 433
Wh
watt-hour. 73, 97, 98, 110, 175, 176, 438
Wien law
describes the wavelength for which the Planck spectrum is at maximum brightness. It is roughly 2.9 mm divided by the blackbody temperature, in Kelvin. 199
work
is a mechanical expression of energy, defined as a force (Newtons) times distance (meters) through which the force acts (along the same direction). The resulting unit is the Joule. 68, 84, 89, 174, 248, 379, 427